Abstract Fault tolerant controllers, based on the Continuous Twisting Algorithm (CTA), are designed for robust stabilization of a three-degree-of-freedom (3-DoF) helicopter prototype. Voltage variations (faults) in the actuators are detected and isolated by means of residual-based equations and exploiting the third-order sliding mode differentiator (SMD). Proposed fault detection and isolation (FDI) scheme is tested with intermittent and persistent faults induced by software. A unknown-input sliding mode observer (SMO) is developed to compare and highlight the performance of the proposed FDI-SMD respect to the classic FDI-SMO. Finally, simulations and real-time experiments confirm that CTA-based controllers counteract additive faults. Filtering the signals from residual equations is suggested in order to mitigate the effects of noises and neglected (parasitic) dynamics on the detectors.

中文翻译：

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基于连续扭转算法的三自由度直升机样机容错控制

摘要 基于连续扭曲算法 (CTA) 的容错控制器设计用于三自由度 (3-DoF) 直升机原型的稳健稳定。通过基于残差的方程并利用三阶滑模微分器 (SMD) 检测和隔离执行器中的电压变化（故障）。建议的故障检测和隔离 (FDI) 方案通过软件引起的间歇性和持续性故障进行测试。开发了一个未知输入滑模观测器 (SMO) 来比较和突出所提出的 FDI-SMD 相对于经典 FDI-SMO 的性能。最后，模拟和实时实验证实基于 CTA 的控制器可以抵消附加故障。